1 /*
2  * Copyright 2004-2008 Freescale Semiconductor, Inc.
3  * Copyright 2009 Semihalf.
4  *
5  * Approved as OSADL project by a majority of OSADL members and funded
6  * by OSADL membership fees in 2009;  for details see www.osadl.org.
7  *
8  * Based on original driver from Freescale Semiconductor
9  * written by John Rigby <jrigby@freescale.com> on basis
10  * of drivers/mtd/nand/mxc_nand.c. Reworked and extended
11  * Piotr Ziecik <kosmo@semihalf.com>.
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License
15  * as published by the Free Software Foundation; either version 2
16  * of the License, or (at your option) any later version.
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
25  * MA 02110-1301, USA.
26  */
27 
28 #include <linux/module.h>
29 #include <linux/clk.h>
30 #include <linux/gfp.h>
31 #include <linux/delay.h>
32 #include <linux/err.h>
33 #include <linux/init.h>
34 #include <linux/interrupt.h>
35 #include <linux/io.h>
36 #include <linux/mtd/mtd.h>
37 #include <linux/mtd/nand.h>
38 #include <linux/mtd/partitions.h>
39 #include <linux/of_device.h>
40 #include <linux/of_platform.h>
41 
42 #include <asm/mpc5121.h>
43 
44 /* Addresses for NFC MAIN RAM BUFFER areas */
45 #define NFC_MAIN_AREA(n)	((n) *  0x200)
46 
47 /* Addresses for NFC SPARE BUFFER areas */
48 #define NFC_SPARE_BUFFERS	8
49 #define NFC_SPARE_LEN		0x40
50 #define NFC_SPARE_AREA(n)	(0x1000 + ((n) * NFC_SPARE_LEN))
51 
52 /* MPC5121 NFC registers */
53 #define NFC_BUF_ADDR		0x1E04
54 #define NFC_FLASH_ADDR		0x1E06
55 #define NFC_FLASH_CMD		0x1E08
56 #define NFC_CONFIG		0x1E0A
57 #define NFC_ECC_STATUS1		0x1E0C
58 #define NFC_ECC_STATUS2		0x1E0E
59 #define NFC_SPAS		0x1E10
60 #define NFC_WRPROT		0x1E12
61 #define NFC_NF_WRPRST		0x1E18
62 #define NFC_CONFIG1		0x1E1A
63 #define NFC_CONFIG2		0x1E1C
64 #define NFC_UNLOCKSTART_BLK0	0x1E20
65 #define NFC_UNLOCKEND_BLK0	0x1E22
66 #define NFC_UNLOCKSTART_BLK1	0x1E24
67 #define NFC_UNLOCKEND_BLK1	0x1E26
68 #define NFC_UNLOCKSTART_BLK2	0x1E28
69 #define NFC_UNLOCKEND_BLK2	0x1E2A
70 #define NFC_UNLOCKSTART_BLK3	0x1E2C
71 #define NFC_UNLOCKEND_BLK3	0x1E2E
72 
73 /* Bit Definitions: NFC_BUF_ADDR */
74 #define NFC_RBA_MASK		(7 << 0)
75 #define NFC_ACTIVE_CS_SHIFT	5
76 #define NFC_ACTIVE_CS_MASK	(3 << NFC_ACTIVE_CS_SHIFT)
77 
78 /* Bit Definitions: NFC_CONFIG */
79 #define NFC_BLS_UNLOCKED	(1 << 1)
80 
81 /* Bit Definitions: NFC_CONFIG1 */
82 #define NFC_ECC_4BIT		(1 << 0)
83 #define NFC_FULL_PAGE_DMA	(1 << 1)
84 #define NFC_SPARE_ONLY		(1 << 2)
85 #define NFC_ECC_ENABLE		(1 << 3)
86 #define NFC_INT_MASK		(1 << 4)
87 #define NFC_BIG_ENDIAN		(1 << 5)
88 #define NFC_RESET		(1 << 6)
89 #define NFC_CE			(1 << 7)
90 #define NFC_ONE_CYCLE		(1 << 8)
91 #define NFC_PPB_32		(0 << 9)
92 #define NFC_PPB_64		(1 << 9)
93 #define NFC_PPB_128		(2 << 9)
94 #define NFC_PPB_256		(3 << 9)
95 #define NFC_PPB_MASK		(3 << 9)
96 #define NFC_FULL_PAGE_INT	(1 << 11)
97 
98 /* Bit Definitions: NFC_CONFIG2 */
99 #define NFC_COMMAND		(1 << 0)
100 #define NFC_ADDRESS		(1 << 1)
101 #define NFC_INPUT		(1 << 2)
102 #define NFC_OUTPUT		(1 << 3)
103 #define NFC_ID			(1 << 4)
104 #define NFC_STATUS		(1 << 5)
105 #define NFC_CMD_FAIL		(1 << 15)
106 #define NFC_INT			(1 << 15)
107 
108 /* Bit Definitions: NFC_WRPROT */
109 #define NFC_WPC_LOCK_TIGHT	(1 << 0)
110 #define NFC_WPC_LOCK		(1 << 1)
111 #define NFC_WPC_UNLOCK		(1 << 2)
112 
113 #define	DRV_NAME		"mpc5121_nfc"
114 
115 /* Timeouts */
116 #define NFC_RESET_TIMEOUT	1000		/* 1 ms */
117 #define NFC_TIMEOUT		(HZ / 10)	/* 1/10 s */
118 
119 struct mpc5121_nfc_prv {
120 	struct mtd_info		mtd;
121 	struct nand_chip	chip;
122 	int			irq;
123 	void __iomem		*regs;
124 	struct clk		*clk;
125 	wait_queue_head_t	irq_waitq;
126 	uint			column;
127 	int			spareonly;
128 	void __iomem		*csreg;
129 	struct device		*dev;
130 };
131 
132 static void mpc5121_nfc_done(struct mtd_info *mtd);
133 
134 /* Read NFC register */
nfc_read(struct mtd_info * mtd,uint reg)135 static inline u16 nfc_read(struct mtd_info *mtd, uint reg)
136 {
137 	struct nand_chip *chip = mtd->priv;
138 	struct mpc5121_nfc_prv *prv = chip->priv;
139 
140 	return in_be16(prv->regs + reg);
141 }
142 
143 /* Write NFC register */
nfc_write(struct mtd_info * mtd,uint reg,u16 val)144 static inline void nfc_write(struct mtd_info *mtd, uint reg, u16 val)
145 {
146 	struct nand_chip *chip = mtd->priv;
147 	struct mpc5121_nfc_prv *prv = chip->priv;
148 
149 	out_be16(prv->regs + reg, val);
150 }
151 
152 /* Set bits in NFC register */
nfc_set(struct mtd_info * mtd,uint reg,u16 bits)153 static inline void nfc_set(struct mtd_info *mtd, uint reg, u16 bits)
154 {
155 	nfc_write(mtd, reg, nfc_read(mtd, reg) | bits);
156 }
157 
158 /* Clear bits in NFC register */
nfc_clear(struct mtd_info * mtd,uint reg,u16 bits)159 static inline void nfc_clear(struct mtd_info *mtd, uint reg, u16 bits)
160 {
161 	nfc_write(mtd, reg, nfc_read(mtd, reg) & ~bits);
162 }
163 
164 /* Invoke address cycle */
mpc5121_nfc_send_addr(struct mtd_info * mtd,u16 addr)165 static inline void mpc5121_nfc_send_addr(struct mtd_info *mtd, u16 addr)
166 {
167 	nfc_write(mtd, NFC_FLASH_ADDR, addr);
168 	nfc_write(mtd, NFC_CONFIG2, NFC_ADDRESS);
169 	mpc5121_nfc_done(mtd);
170 }
171 
172 /* Invoke command cycle */
mpc5121_nfc_send_cmd(struct mtd_info * mtd,u16 cmd)173 static inline void mpc5121_nfc_send_cmd(struct mtd_info *mtd, u16 cmd)
174 {
175 	nfc_write(mtd, NFC_FLASH_CMD, cmd);
176 	nfc_write(mtd, NFC_CONFIG2, NFC_COMMAND);
177 	mpc5121_nfc_done(mtd);
178 }
179 
180 /* Send data from NFC buffers to NAND flash */
mpc5121_nfc_send_prog_page(struct mtd_info * mtd)181 static inline void mpc5121_nfc_send_prog_page(struct mtd_info *mtd)
182 {
183 	nfc_clear(mtd, NFC_BUF_ADDR, NFC_RBA_MASK);
184 	nfc_write(mtd, NFC_CONFIG2, NFC_INPUT);
185 	mpc5121_nfc_done(mtd);
186 }
187 
188 /* Receive data from NAND flash */
mpc5121_nfc_send_read_page(struct mtd_info * mtd)189 static inline void mpc5121_nfc_send_read_page(struct mtd_info *mtd)
190 {
191 	nfc_clear(mtd, NFC_BUF_ADDR, NFC_RBA_MASK);
192 	nfc_write(mtd, NFC_CONFIG2, NFC_OUTPUT);
193 	mpc5121_nfc_done(mtd);
194 }
195 
196 /* Receive ID from NAND flash */
mpc5121_nfc_send_read_id(struct mtd_info * mtd)197 static inline void mpc5121_nfc_send_read_id(struct mtd_info *mtd)
198 {
199 	nfc_clear(mtd, NFC_BUF_ADDR, NFC_RBA_MASK);
200 	nfc_write(mtd, NFC_CONFIG2, NFC_ID);
201 	mpc5121_nfc_done(mtd);
202 }
203 
204 /* Receive status from NAND flash */
mpc5121_nfc_send_read_status(struct mtd_info * mtd)205 static inline void mpc5121_nfc_send_read_status(struct mtd_info *mtd)
206 {
207 	nfc_clear(mtd, NFC_BUF_ADDR, NFC_RBA_MASK);
208 	nfc_write(mtd, NFC_CONFIG2, NFC_STATUS);
209 	mpc5121_nfc_done(mtd);
210 }
211 
212 /* NFC interrupt handler */
mpc5121_nfc_irq(int irq,void * data)213 static irqreturn_t mpc5121_nfc_irq(int irq, void *data)
214 {
215 	struct mtd_info *mtd = data;
216 	struct nand_chip *chip = mtd->priv;
217 	struct mpc5121_nfc_prv *prv = chip->priv;
218 
219 	nfc_set(mtd, NFC_CONFIG1, NFC_INT_MASK);
220 	wake_up(&prv->irq_waitq);
221 
222 	return IRQ_HANDLED;
223 }
224 
225 /* Wait for operation complete */
mpc5121_nfc_done(struct mtd_info * mtd)226 static void mpc5121_nfc_done(struct mtd_info *mtd)
227 {
228 	struct nand_chip *chip = mtd->priv;
229 	struct mpc5121_nfc_prv *prv = chip->priv;
230 	int rv;
231 
232 	if ((nfc_read(mtd, NFC_CONFIG2) & NFC_INT) == 0) {
233 		nfc_clear(mtd, NFC_CONFIG1, NFC_INT_MASK);
234 		rv = wait_event_timeout(prv->irq_waitq,
235 			(nfc_read(mtd, NFC_CONFIG2) & NFC_INT), NFC_TIMEOUT);
236 
237 		if (!rv)
238 			dev_warn(prv->dev,
239 				"Timeout while waiting for interrupt.\n");
240 	}
241 
242 	nfc_clear(mtd, NFC_CONFIG2, NFC_INT);
243 }
244 
245 /* Do address cycle(s) */
mpc5121_nfc_addr_cycle(struct mtd_info * mtd,int column,int page)246 static void mpc5121_nfc_addr_cycle(struct mtd_info *mtd, int column, int page)
247 {
248 	struct nand_chip *chip = mtd->priv;
249 	u32 pagemask = chip->pagemask;
250 
251 	if (column != -1) {
252 		mpc5121_nfc_send_addr(mtd, column);
253 		if (mtd->writesize > 512)
254 			mpc5121_nfc_send_addr(mtd, column >> 8);
255 	}
256 
257 	if (page != -1) {
258 		do {
259 			mpc5121_nfc_send_addr(mtd, page & 0xFF);
260 			page >>= 8;
261 			pagemask >>= 8;
262 		} while (pagemask);
263 	}
264 }
265 
266 /* Control chip select signals */
mpc5121_nfc_select_chip(struct mtd_info * mtd,int chip)267 static void mpc5121_nfc_select_chip(struct mtd_info *mtd, int chip)
268 {
269 	if (chip < 0) {
270 		nfc_clear(mtd, NFC_CONFIG1, NFC_CE);
271 		return;
272 	}
273 
274 	nfc_clear(mtd, NFC_BUF_ADDR, NFC_ACTIVE_CS_MASK);
275 	nfc_set(mtd, NFC_BUF_ADDR, (chip << NFC_ACTIVE_CS_SHIFT) &
276 							NFC_ACTIVE_CS_MASK);
277 	nfc_set(mtd, NFC_CONFIG1, NFC_CE);
278 }
279 
280 /* Init external chip select logic on ADS5121 board */
ads5121_chipselect_init(struct mtd_info * mtd)281 static int ads5121_chipselect_init(struct mtd_info *mtd)
282 {
283 	struct nand_chip *chip = mtd->priv;
284 	struct mpc5121_nfc_prv *prv = chip->priv;
285 	struct device_node *dn;
286 
287 	dn = of_find_compatible_node(NULL, NULL, "fsl,mpc5121ads-cpld");
288 	if (dn) {
289 		prv->csreg = of_iomap(dn, 0);
290 		of_node_put(dn);
291 		if (!prv->csreg)
292 			return -ENOMEM;
293 
294 		/* CPLD Register 9 controls NAND /CE Lines */
295 		prv->csreg += 9;
296 		return 0;
297 	}
298 
299 	return -EINVAL;
300 }
301 
302 /* Control chips select signal on ADS5121 board */
ads5121_select_chip(struct mtd_info * mtd,int chip)303 static void ads5121_select_chip(struct mtd_info *mtd, int chip)
304 {
305 	struct nand_chip *nand = mtd->priv;
306 	struct mpc5121_nfc_prv *prv = nand->priv;
307 	u8 v;
308 
309 	v = in_8(prv->csreg);
310 	v |= 0x0F;
311 
312 	if (chip >= 0) {
313 		mpc5121_nfc_select_chip(mtd, 0);
314 		v &= ~(1 << chip);
315 	} else
316 		mpc5121_nfc_select_chip(mtd, -1);
317 
318 	out_8(prv->csreg, v);
319 }
320 
321 /* Read NAND Ready/Busy signal */
mpc5121_nfc_dev_ready(struct mtd_info * mtd)322 static int mpc5121_nfc_dev_ready(struct mtd_info *mtd)
323 {
324 	/*
325 	 * NFC handles ready/busy signal internally. Therefore, this function
326 	 * always returns status as ready.
327 	 */
328 	return 1;
329 }
330 
331 /* Write command to NAND flash */
mpc5121_nfc_command(struct mtd_info * mtd,unsigned command,int column,int page)332 static void mpc5121_nfc_command(struct mtd_info *mtd, unsigned command,
333 							int column, int page)
334 {
335 	struct nand_chip *chip = mtd->priv;
336 	struct mpc5121_nfc_prv *prv = chip->priv;
337 
338 	prv->column = (column >= 0) ? column : 0;
339 	prv->spareonly = 0;
340 
341 	switch (command) {
342 	case NAND_CMD_PAGEPROG:
343 		mpc5121_nfc_send_prog_page(mtd);
344 		break;
345 	/*
346 	 * NFC does not support sub-page reads and writes,
347 	 * so emulate them using full page transfers.
348 	 */
349 	case NAND_CMD_READ0:
350 		column = 0;
351 		break;
352 
353 	case NAND_CMD_READ1:
354 		prv->column += 256;
355 		command = NAND_CMD_READ0;
356 		column = 0;
357 		break;
358 
359 	case NAND_CMD_READOOB:
360 		prv->spareonly = 1;
361 		command = NAND_CMD_READ0;
362 		column = 0;
363 		break;
364 
365 	case NAND_CMD_SEQIN:
366 		mpc5121_nfc_command(mtd, NAND_CMD_READ0, column, page);
367 		column = 0;
368 		break;
369 
370 	case NAND_CMD_ERASE1:
371 	case NAND_CMD_ERASE2:
372 	case NAND_CMD_READID:
373 	case NAND_CMD_STATUS:
374 		break;
375 
376 	default:
377 		return;
378 	}
379 
380 	mpc5121_nfc_send_cmd(mtd, command);
381 	mpc5121_nfc_addr_cycle(mtd, column, page);
382 
383 	switch (command) {
384 	case NAND_CMD_READ0:
385 		if (mtd->writesize > 512)
386 			mpc5121_nfc_send_cmd(mtd, NAND_CMD_READSTART);
387 		mpc5121_nfc_send_read_page(mtd);
388 		break;
389 
390 	case NAND_CMD_READID:
391 		mpc5121_nfc_send_read_id(mtd);
392 		break;
393 
394 	case NAND_CMD_STATUS:
395 		mpc5121_nfc_send_read_status(mtd);
396 		if (chip->options & NAND_BUSWIDTH_16)
397 			prv->column = 1;
398 		else
399 			prv->column = 0;
400 		break;
401 	}
402 }
403 
404 /* Copy data from/to NFC spare buffers. */
mpc5121_nfc_copy_spare(struct mtd_info * mtd,uint offset,u8 * buffer,uint size,int wr)405 static void mpc5121_nfc_copy_spare(struct mtd_info *mtd, uint offset,
406 						u8 *buffer, uint size, int wr)
407 {
408 	struct nand_chip *nand = mtd->priv;
409 	struct mpc5121_nfc_prv *prv = nand->priv;
410 	uint o, s, sbsize, blksize;
411 
412 	/*
413 	 * NAND spare area is available through NFC spare buffers.
414 	 * The NFC divides spare area into (page_size / 512) chunks.
415 	 * Each chunk is placed into separate spare memory area, using
416 	 * first (spare_size / num_of_chunks) bytes of the buffer.
417 	 *
418 	 * For NAND device in which the spare area is not divided fully
419 	 * by the number of chunks, number of used bytes in each spare
420 	 * buffer is rounded down to the nearest even number of bytes,
421 	 * and all remaining bytes are added to the last used spare area.
422 	 *
423 	 * For more information read section 26.6.10 of MPC5121e
424 	 * Microcontroller Reference Manual, Rev. 3.
425 	 */
426 
427 	/* Calculate number of valid bytes in each spare buffer */
428 	sbsize = (mtd->oobsize / (mtd->writesize / 512)) & ~1;
429 
430 	while (size) {
431 		/* Calculate spare buffer number */
432 		s = offset / sbsize;
433 		if (s > NFC_SPARE_BUFFERS - 1)
434 			s = NFC_SPARE_BUFFERS - 1;
435 
436 		/*
437 		 * Calculate offset to requested data block in selected spare
438 		 * buffer and its size.
439 		 */
440 		o = offset - (s * sbsize);
441 		blksize = min(sbsize - o, size);
442 
443 		if (wr)
444 			memcpy_toio(prv->regs + NFC_SPARE_AREA(s) + o,
445 							buffer, blksize);
446 		else
447 			memcpy_fromio(buffer,
448 				prv->regs + NFC_SPARE_AREA(s) + o, blksize);
449 
450 		buffer += blksize;
451 		offset += blksize;
452 		size -= blksize;
453 	};
454 }
455 
456 /* Copy data from/to NFC main and spare buffers */
mpc5121_nfc_buf_copy(struct mtd_info * mtd,u_char * buf,int len,int wr)457 static void mpc5121_nfc_buf_copy(struct mtd_info *mtd, u_char *buf, int len,
458 									int wr)
459 {
460 	struct nand_chip *chip = mtd->priv;
461 	struct mpc5121_nfc_prv *prv = chip->priv;
462 	uint c = prv->column;
463 	uint l;
464 
465 	/* Handle spare area access */
466 	if (prv->spareonly || c >= mtd->writesize) {
467 		/* Calculate offset from beginning of spare area */
468 		if (c >= mtd->writesize)
469 			c -= mtd->writesize;
470 
471 		prv->column += len;
472 		mpc5121_nfc_copy_spare(mtd, c, buf, len, wr);
473 		return;
474 	}
475 
476 	/*
477 	 * Handle main area access - limit copy length to prevent
478 	 * crossing main/spare boundary.
479 	 */
480 	l = min((uint)len, mtd->writesize - c);
481 	prv->column += l;
482 
483 	if (wr)
484 		memcpy_toio(prv->regs + NFC_MAIN_AREA(0) + c, buf, l);
485 	else
486 		memcpy_fromio(buf, prv->regs + NFC_MAIN_AREA(0) + c, l);
487 
488 	/* Handle crossing main/spare boundary */
489 	if (l != len) {
490 		buf += l;
491 		len -= l;
492 		mpc5121_nfc_buf_copy(mtd, buf, len, wr);
493 	}
494 }
495 
496 /* Read data from NFC buffers */
mpc5121_nfc_read_buf(struct mtd_info * mtd,u_char * buf,int len)497 static void mpc5121_nfc_read_buf(struct mtd_info *mtd, u_char *buf, int len)
498 {
499 	mpc5121_nfc_buf_copy(mtd, buf, len, 0);
500 }
501 
502 /* Write data to NFC buffers */
mpc5121_nfc_write_buf(struct mtd_info * mtd,const u_char * buf,int len)503 static void mpc5121_nfc_write_buf(struct mtd_info *mtd,
504 						const u_char *buf, int len)
505 {
506 	mpc5121_nfc_buf_copy(mtd, (u_char *)buf, len, 1);
507 }
508 
509 /* Compare buffer with NAND flash */
mpc5121_nfc_verify_buf(struct mtd_info * mtd,const u_char * buf,int len)510 static int mpc5121_nfc_verify_buf(struct mtd_info *mtd,
511 						const u_char *buf, int len)
512 {
513 	u_char tmp[256];
514 	uint bsize;
515 
516 	while (len) {
517 		bsize = min(len, 256);
518 		mpc5121_nfc_read_buf(mtd, tmp, bsize);
519 
520 		if (memcmp(buf, tmp, bsize))
521 			return 1;
522 
523 		buf += bsize;
524 		len -= bsize;
525 	}
526 
527 	return 0;
528 }
529 
530 /* Read byte from NFC buffers */
mpc5121_nfc_read_byte(struct mtd_info * mtd)531 static u8 mpc5121_nfc_read_byte(struct mtd_info *mtd)
532 {
533 	u8 tmp;
534 
535 	mpc5121_nfc_read_buf(mtd, &tmp, sizeof(tmp));
536 
537 	return tmp;
538 }
539 
540 /* Read word from NFC buffers */
mpc5121_nfc_read_word(struct mtd_info * mtd)541 static u16 mpc5121_nfc_read_word(struct mtd_info *mtd)
542 {
543 	u16 tmp;
544 
545 	mpc5121_nfc_read_buf(mtd, (u_char *)&tmp, sizeof(tmp));
546 
547 	return tmp;
548 }
549 
550 /*
551  * Read NFC configuration from Reset Config Word
552  *
553  * NFC is configured during reset in basis of information stored
554  * in Reset Config Word. There is no other way to set NAND block
555  * size, spare size and bus width.
556  */
mpc5121_nfc_read_hw_config(struct mtd_info * mtd)557 static int mpc5121_nfc_read_hw_config(struct mtd_info *mtd)
558 {
559 	struct nand_chip *chip = mtd->priv;
560 	struct mpc5121_nfc_prv *prv = chip->priv;
561 	struct mpc512x_reset_module *rm;
562 	struct device_node *rmnode;
563 	uint rcw_pagesize = 0;
564 	uint rcw_sparesize = 0;
565 	uint rcw_width;
566 	uint rcwh;
567 	uint romloc, ps;
568 	int ret = 0;
569 
570 	rmnode = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-reset");
571 	if (!rmnode) {
572 		dev_err(prv->dev, "Missing 'fsl,mpc5121-reset' "
573 					"node in device tree!\n");
574 		return -ENODEV;
575 	}
576 
577 	rm = of_iomap(rmnode, 0);
578 	if (!rm) {
579 		dev_err(prv->dev, "Error mapping reset module node!\n");
580 		ret = -EBUSY;
581 		goto out;
582 	}
583 
584 	rcwh = in_be32(&rm->rcwhr);
585 
586 	/* Bit 6: NFC bus width */
587 	rcw_width = ((rcwh >> 6) & 0x1) ? 2 : 1;
588 
589 	/* Bit 7: NFC Page/Spare size */
590 	ps = (rcwh >> 7) & 0x1;
591 
592 	/* Bits [22:21]: ROM Location */
593 	romloc = (rcwh >> 21) & 0x3;
594 
595 	/* Decode RCW bits */
596 	switch ((ps << 2) | romloc) {
597 	case 0x00:
598 	case 0x01:
599 		rcw_pagesize = 512;
600 		rcw_sparesize = 16;
601 		break;
602 	case 0x02:
603 	case 0x03:
604 		rcw_pagesize = 4096;
605 		rcw_sparesize = 128;
606 		break;
607 	case 0x04:
608 	case 0x05:
609 		rcw_pagesize = 2048;
610 		rcw_sparesize = 64;
611 		break;
612 	case 0x06:
613 	case 0x07:
614 		rcw_pagesize = 4096;
615 		rcw_sparesize = 218;
616 		break;
617 	}
618 
619 	mtd->writesize = rcw_pagesize;
620 	mtd->oobsize = rcw_sparesize;
621 	if (rcw_width == 2)
622 		chip->options |= NAND_BUSWIDTH_16;
623 
624 	dev_notice(prv->dev, "Configured for "
625 				"%u-bit NAND, page size %u "
626 				"with %u spare.\n",
627 				rcw_width * 8, rcw_pagesize,
628 				rcw_sparesize);
629 	iounmap(rm);
630 out:
631 	of_node_put(rmnode);
632 	return ret;
633 }
634 
635 /* Free driver resources */
mpc5121_nfc_free(struct device * dev,struct mtd_info * mtd)636 static void mpc5121_nfc_free(struct device *dev, struct mtd_info *mtd)
637 {
638 	struct nand_chip *chip = mtd->priv;
639 	struct mpc5121_nfc_prv *prv = chip->priv;
640 
641 	if (prv->clk) {
642 		clk_disable(prv->clk);
643 		clk_put(prv->clk);
644 	}
645 
646 	if (prv->csreg)
647 		iounmap(prv->csreg);
648 }
649 
mpc5121_nfc_probe(struct platform_device * op)650 static int __devinit mpc5121_nfc_probe(struct platform_device *op)
651 {
652 	struct device_node *rootnode, *dn = op->dev.of_node;
653 	struct device *dev = &op->dev;
654 	struct mpc5121_nfc_prv *prv;
655 	struct resource res;
656 	struct mtd_info *mtd;
657 	struct nand_chip *chip;
658 	unsigned long regs_paddr, regs_size;
659 	const __be32 *chips_no;
660 	int resettime = 0;
661 	int retval = 0;
662 	int rev, len;
663 	struct mtd_part_parser_data ppdata;
664 
665 	/*
666 	 * Check SoC revision. This driver supports only NFC
667 	 * in MPC5121 revision 2 and MPC5123 revision 3.
668 	 */
669 	rev = (mfspr(SPRN_SVR) >> 4) & 0xF;
670 	if ((rev != 2) && (rev != 3)) {
671 		dev_err(dev, "SoC revision %u is not supported!\n", rev);
672 		return -ENXIO;
673 	}
674 
675 	prv = devm_kzalloc(dev, sizeof(*prv), GFP_KERNEL);
676 	if (!prv) {
677 		dev_err(dev, "Memory exhausted!\n");
678 		return -ENOMEM;
679 	}
680 
681 	mtd = &prv->mtd;
682 	chip = &prv->chip;
683 
684 	mtd->priv = chip;
685 	chip->priv = prv;
686 	prv->dev = dev;
687 
688 	/* Read NFC configuration from Reset Config Word */
689 	retval = mpc5121_nfc_read_hw_config(mtd);
690 	if (retval) {
691 		dev_err(dev, "Unable to read NFC config!\n");
692 		return retval;
693 	}
694 
695 	prv->irq = irq_of_parse_and_map(dn, 0);
696 	if (prv->irq == NO_IRQ) {
697 		dev_err(dev, "Error mapping IRQ!\n");
698 		return -EINVAL;
699 	}
700 
701 	retval = of_address_to_resource(dn, 0, &res);
702 	if (retval) {
703 		dev_err(dev, "Error parsing memory region!\n");
704 		return retval;
705 	}
706 
707 	chips_no = of_get_property(dn, "chips", &len);
708 	if (!chips_no || len != sizeof(*chips_no)) {
709 		dev_err(dev, "Invalid/missing 'chips' property!\n");
710 		return -EINVAL;
711 	}
712 
713 	regs_paddr = res.start;
714 	regs_size = resource_size(&res);
715 
716 	if (!devm_request_mem_region(dev, regs_paddr, regs_size, DRV_NAME)) {
717 		dev_err(dev, "Error requesting memory region!\n");
718 		return -EBUSY;
719 	}
720 
721 	prv->regs = devm_ioremap(dev, regs_paddr, regs_size);
722 	if (!prv->regs) {
723 		dev_err(dev, "Error mapping memory region!\n");
724 		return -ENOMEM;
725 	}
726 
727 	mtd->name = "MPC5121 NAND";
728 	ppdata.of_node = dn;
729 	chip->dev_ready = mpc5121_nfc_dev_ready;
730 	chip->cmdfunc = mpc5121_nfc_command;
731 	chip->read_byte = mpc5121_nfc_read_byte;
732 	chip->read_word = mpc5121_nfc_read_word;
733 	chip->read_buf = mpc5121_nfc_read_buf;
734 	chip->write_buf = mpc5121_nfc_write_buf;
735 	chip->verify_buf = mpc5121_nfc_verify_buf;
736 	chip->select_chip = mpc5121_nfc_select_chip;
737 	chip->options = NAND_NO_AUTOINCR;
738 	chip->bbt_options = NAND_BBT_USE_FLASH;
739 	chip->ecc.mode = NAND_ECC_SOFT;
740 
741 	/* Support external chip-select logic on ADS5121 board */
742 	rootnode = of_find_node_by_path("/");
743 	if (of_device_is_compatible(rootnode, "fsl,mpc5121ads")) {
744 		retval = ads5121_chipselect_init(mtd);
745 		if (retval) {
746 			dev_err(dev, "Chipselect init error!\n");
747 			of_node_put(rootnode);
748 			return retval;
749 		}
750 
751 		chip->select_chip = ads5121_select_chip;
752 	}
753 	of_node_put(rootnode);
754 
755 	/* Enable NFC clock */
756 	prv->clk = clk_get(dev, "nfc_clk");
757 	if (IS_ERR(prv->clk)) {
758 		dev_err(dev, "Unable to acquire NFC clock!\n");
759 		retval = PTR_ERR(prv->clk);
760 		goto error;
761 	}
762 
763 	clk_enable(prv->clk);
764 
765 	/* Reset NAND Flash controller */
766 	nfc_set(mtd, NFC_CONFIG1, NFC_RESET);
767 	while (nfc_read(mtd, NFC_CONFIG1) & NFC_RESET) {
768 		if (resettime++ >= NFC_RESET_TIMEOUT) {
769 			dev_err(dev, "Timeout while resetting NFC!\n");
770 			retval = -EINVAL;
771 			goto error;
772 		}
773 
774 		udelay(1);
775 	}
776 
777 	/* Enable write to NFC memory */
778 	nfc_write(mtd, NFC_CONFIG, NFC_BLS_UNLOCKED);
779 
780 	/* Enable write to all NAND pages */
781 	nfc_write(mtd, NFC_UNLOCKSTART_BLK0, 0x0000);
782 	nfc_write(mtd, NFC_UNLOCKEND_BLK0, 0xFFFF);
783 	nfc_write(mtd, NFC_WRPROT, NFC_WPC_UNLOCK);
784 
785 	/*
786 	 * Setup NFC:
787 	 *	- Big Endian transfers,
788 	 *	- Interrupt after full page read/write.
789 	 */
790 	nfc_write(mtd, NFC_CONFIG1, NFC_BIG_ENDIAN | NFC_INT_MASK |
791 							NFC_FULL_PAGE_INT);
792 
793 	/* Set spare area size */
794 	nfc_write(mtd, NFC_SPAS, mtd->oobsize >> 1);
795 
796 	init_waitqueue_head(&prv->irq_waitq);
797 	retval = devm_request_irq(dev, prv->irq, &mpc5121_nfc_irq, 0, DRV_NAME,
798 									mtd);
799 	if (retval) {
800 		dev_err(dev, "Error requesting IRQ!\n");
801 		goto error;
802 	}
803 
804 	/* Detect NAND chips */
805 	if (nand_scan(mtd, be32_to_cpup(chips_no))) {
806 		dev_err(dev, "NAND Flash not found !\n");
807 		devm_free_irq(dev, prv->irq, mtd);
808 		retval = -ENXIO;
809 		goto error;
810 	}
811 
812 	/* Set erase block size */
813 	switch (mtd->erasesize / mtd->writesize) {
814 	case 32:
815 		nfc_set(mtd, NFC_CONFIG1, NFC_PPB_32);
816 		break;
817 
818 	case 64:
819 		nfc_set(mtd, NFC_CONFIG1, NFC_PPB_64);
820 		break;
821 
822 	case 128:
823 		nfc_set(mtd, NFC_CONFIG1, NFC_PPB_128);
824 		break;
825 
826 	case 256:
827 		nfc_set(mtd, NFC_CONFIG1, NFC_PPB_256);
828 		break;
829 
830 	default:
831 		dev_err(dev, "Unsupported NAND flash!\n");
832 		devm_free_irq(dev, prv->irq, mtd);
833 		retval = -ENXIO;
834 		goto error;
835 	}
836 
837 	dev_set_drvdata(dev, mtd);
838 
839 	/* Register device in MTD */
840 	retval = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
841 	if (retval) {
842 		dev_err(dev, "Error adding MTD device!\n");
843 		devm_free_irq(dev, prv->irq, mtd);
844 		goto error;
845 	}
846 
847 	return 0;
848 error:
849 	mpc5121_nfc_free(dev, mtd);
850 	return retval;
851 }
852 
mpc5121_nfc_remove(struct platform_device * op)853 static int __devexit mpc5121_nfc_remove(struct platform_device *op)
854 {
855 	struct device *dev = &op->dev;
856 	struct mtd_info *mtd = dev_get_drvdata(dev);
857 	struct nand_chip *chip = mtd->priv;
858 	struct mpc5121_nfc_prv *prv = chip->priv;
859 
860 	nand_release(mtd);
861 	devm_free_irq(dev, prv->irq, mtd);
862 	mpc5121_nfc_free(dev, mtd);
863 
864 	return 0;
865 }
866 
867 static struct of_device_id mpc5121_nfc_match[] __devinitdata = {
868 	{ .compatible = "fsl,mpc5121-nfc", },
869 	{},
870 };
871 
872 static struct platform_driver mpc5121_nfc_driver = {
873 	.probe		= mpc5121_nfc_probe,
874 	.remove		= __devexit_p(mpc5121_nfc_remove),
875 	.driver		= {
876 		.name = DRV_NAME,
877 		.owner = THIS_MODULE,
878 		.of_match_table = mpc5121_nfc_match,
879 	},
880 };
881 
882 module_platform_driver(mpc5121_nfc_driver);
883 
884 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
885 MODULE_DESCRIPTION("MPC5121 NAND MTD driver");
886 MODULE_LICENSE("GPL");
887